1. Field of the Invention
This invention relates to methods of and apparatus for automatically grinding cathode ray tube (CRT) faceplates, and more particularly, to methods and apparatus for assigning and delivering CRT faceplates to designated ones of a plurality of grinding machines, identifying the machine in which a CRT faceplate is ground, loading the CRT faceplate into the machines, and removing CRT faceplates from the machines.
2. Description of the Related Art
Heretofore, it has been known to grind the outer surface of the faceplates of CRTs to improve the optical quality of the images formed upon the faceplates. Such grinding operations have been performed in grinding machines of various forms including machines, hereinafter designated "singlehead grinders", having a single elastomeric wheel, rotating around a generally horizontal axis, and to which a slurry of abrasive is fed while a carriage is traversed in a generally horizontal plane to carry a rotating CRT faceplate chuck beneath the wheel so that the wheel rides over the contour of a suitably chucked faceplate. In production, an aligned array of singlehead grinders are positioned adjacent a conveyor for CRT faceplates which furnishes raw or unground faceplates to the area and carries ground faceplates from the area. An attendant transferred faceplates from the conveyor to the singlehead grinder, seated them properly in the neat blocks of the grinder chucks, started the grinder after it was properly loaded, and returned to remove the ground faceplate and placed it on the conveyor at the end of the grinder cycle. Since the grinding cycle consumed more time than the faceplate transfers, the attendant was usually assigned to service a plurality of grinders.
Significant time was lost in the manual loading and unloading of the grinders. Ware was occasionally passed through the grinding station without being transferred to the grinders. As CRT faceplates have become larger, the ware is quite heavy and it has become difficult to load into and remove from the grinders. Production rates are dependant upon the skill, strength and endurance of the machine attendants.